JP5329466B2 - Smoke detector - Google Patents

Description

  The present invention relates to a smoke detection device that detects the generation of smoke by performing image processing on an image captured by a surveillance camera, and in particular, displays the detected area on a monitor, thereby allowing the administrator to visually recognize the smoke. The present invention relates to a smoke detection device that improves safety.

  From the viewpoint of initial fire extinguishment in the event of a fire or prevention of escape delay in a fire accident, early detection of fire or smoke is very important. Thus, in the field of smoke detection devices, research has been conducted on early detection of smoke by performing image processing on an image captured by a surveillance camera.

  As an example, there is a conventional smoke detection device that detects smoke by installing a camera in a tunnel or the like and performing image processing on an image captured by the camera. In image processing for detecting smoke, generally, a reference image (reference image) is stored in advance, a difference image between the latest captured image and the reference image is calculated, and a region where a change has occurred is calculated. Extraction detects smoke (for example, see Patent Document 1).

  In addition, the reference image is regularly updated in order to cope with the temporal change of the reference image due to the influence of sunlight.

Thus, by performing image processing on the image captured by the camera and performing smoke detection, the following two merits can be obtained.
1) By visually confirming the image of the surveillance camera, it is possible to grasp the smoke detection status in a remote place.
2) It is possible to divert already installed surveillance cameras and construct efficient equipment.

  In addition, for the purpose of improving detection accuracy, a predetermined detection area is set in the captured range, and calculation by two or more smoke detection determination elements is performed in the detection area, so that different types of smoke are detected. There is one that detects occurrence (see, for example, Patent Document 2). In Patent Document 2, by having two or more smoke detection determination elements, smoke having different characteristics (behavior) such as “flowing smoke” and “slow smoke” can be detected.

  Here, “fluid smoke” is a general term for smoke that is generated from a fire source that is a fire type, and has a characteristic that it is generated in a very short time and has a large and fast movement (flow). is there. On the other hand, “slow smoke” is a general term for smoke that gradually spreads and spreads away from the source of the fire, and has the characteristics that the movement is very slow and the change in time units is scarce. It is what.

  Furthermore, smoke has characteristics that change not only the speed of movement, but also the density, depending on the generation factor. Therefore, for such discrimination of darkness, it is possible to distinguish and detect, for example, “deep slow smoke” and “thin slow smoke” by having two or more smoke detection determination elements. .

Japanese Patent No. 3909665 JP 2008-46107 A

However, the prior art has the following problems.
According to Patent Document 2, it is possible to detect smoke having different characteristics by individually providing an algorithm for detecting a plurality of smoke. When smoke is detected, a warning by a buzzer or the like can be given. In addition, an image within the monitoring range captured by the monitoring camera is displayed on the monitor. However, it does not include a visual display processing means for easily transmitting to a manager or the like what type of smoke is generated at which location.

  The present invention has been made in order to solve the above-described problems, and has made it possible to visually check smoke detection results having different characteristics on a monitor so as to improve visibility. The purpose is to obtain a smoke detector.

  The smoke detection device according to the present invention has two or more smoke detection determination elements for each of a plurality of areas set in an image captured by a surveillance camera, thereby allowing a plurality of types of smoke having different characteristics to be detected. In a smoke detection apparatus including a smoke detection means for identifying and detecting, a mapping means for mapping a region where smoke is detected by the smoke detection means among a plurality of regions, and a mapping for each property by the mapping means Based on the result, an ellipse is generated according to the position and size of the mapped region corresponding to each characteristic, and the generated ellipse is displayed on the monitor that displays the image captured by the monitoring camera. And smoke type display processing means for displaying with different colors or different line types corresponding to.

  According to the smoke detection device of the present invention, an ellipse corresponding to the position and size of each region detected for each characteristic is generated, and a different display color or different line type is used for each characteristic on the monitor screen of the captured image. By providing an ellipse with the function of displaying an oval, it is possible to easily check the smoke detection results having different characteristics on the monitor, and to obtain a smoke detection device with improved visibility.

It is a block diagram of the smoke detection apparatus in Embodiment 1 of this invention. It is explanatory drawing of the specific function of the detection result display process part in Embodiment 1 of this invention. It is explanatory drawing of the specific function of the detection result display process part in Embodiment 1 of this invention.

  Hereinafter, a preferred embodiment of a smoke detection device of the present invention will be described with reference to the drawings.

Embodiment 1 FIG.
FIG. 1 is a configuration diagram of a smoke detection device according to Embodiment 1 of the present invention. The smoke detection device according to the first embodiment includes an image memory 10, a smoke detection unit 20, and a detection result display processing unit 30. The image memory 10 is configured as an image memory for a plurality of frames so that images captured by the camera 1 can be stored as time-series data for a certain period in the past. An image captured by the camera 1 is displayed on the monitor 2.

  The smoke detection unit 20 as the smoke detection means is individually provided with an algorithm for detecting a plurality of smoke having different characteristics. In the example of FIG. 1, the flowing smoke detection means 21, the dark slow smoke detection means 22, and A thin slow smoke detecting means 23 is provided. And each of these detection means 21-23 detects the presence or absence of smoke according to a characteristic with respect to each of the several area | region set in the image imaged with the surveillance camera 1. FIG.

  In addition, the smoke detection function according to the characteristic by this smoke detection part 20 is demonstrated easily below. Since the algorithm of the flowing smoke detection means 21 has only to extract smoke with a large amount of movement, a process for determining whether or not there is a large number of frequencies having a specific luminance value by looking at the histogram for each pixel for a certain time A process of judging whether there is a change by looking at a correlation value with an image, a difference process of an edge amount of a reference image, and the like are provided.

  In the case of the dark slow smoke detecting means 22, it is only necessary to determine that the transmittance is lowered. In the case of the thin slow smoke detecting means 23, it is determined that the transmittance is within a predetermined range, or the edge amount of the image is What is necessary is just to judge that it falls.

  Therefore, the algorithm of the dark slow smoke detecting means 22 and the thin slow smoke detecting means 23 performs frequency analysis on the time series data of the number of pixels in which the determination process based on the transmittance and the luminance change in the detection area have occurred, and the spectrum ratio and spectrum A process for determining the intensity, a process for determining a correlation value with the reference image, a process for determining the edge amount, and the like are provided.

  The detection result display processing unit 30 that is a technical feature of the present invention includes a mapping unit 31 and a smoke type display processing unit 32. The mapping means 31 maps the areas in which smoke is detected by the detection means 21 to 23 of the smoke detection unit 20 among the plurality of areas according to characteristics.

  Then, the smoke type display processing means 32 generates an ellipse according to the position and size of each area detected for each characteristic based on the mapping result for each characteristic, and displays the captured image with a different display color for each characteristic. Display an ellipse on the monitor screen. As described above, the operation of the detection result display processing unit 30 including the mapping unit 31 and the smoke type display processing unit 32 allows the administrator to easily check the detection result of smoke having different characteristics visually on the monitor. become able to.

  Next, a specific display processing function of the detection result display processing unit 30 which is a technical feature of the present invention will be described with reference to the drawings. 2 and 3 are explanatory diagrams of specific functions of the detection result display processing unit 30 according to the first embodiment of the present invention. 2 and 3, a plurality of areas set in advance with respect to the image captured by the camera 1 are represented in a mesh shape, and each square portion corresponds to one area. doing. And this area | region is comprised by the several pixel, and the smoke detection according to the characteristic by the smoke detection part 20 will be performed for every area | region.

  First, basic functions will be described with reference to FIG. In the following example, a region in which the possibility of flowing smoke is determined to be high by the flowing smoke detection means 21 is set as the characteristic 1, and a region in which the possibility of dark slow smoke is determined to be high by the dark slow smoke detection means 22 Is described as characteristic 2. However, the present invention is not limited to the display divided into two characteristics, and the concept described below can be similarly applied to three or more characteristics.

  FIG. 2 (a1) shows a mapping result in which the mapping unit 31 maps, as characteristic 1, an area where the possibility of flowing smoke is determined by the flowing smoke detection unit 21 is high. Similarly, FIG. 2 (a2) shows a mapping result in which the mapping unit 31 maps, as the characteristic 2, a region where the dark slow smoke detection unit 22 has determined that the possibility of dark slow smoke is high.

  For such a mapping result, the smoke type display processing means 32 generates an ellipse corresponding to the position and size of the mapping result. For example, the smoke type display processing means 32 can identify a circumscribed rectangle of the mapped adjacent area and generate an ellipse so as to be inscribed in the identified circumscribed rectangle. 2 (b1) and 2 (b2) show ellipses generated by the smoke type display processing means 32 based on the circumscribed rectangles of the mapping results of FIGS. 2 (a1) and 2 (a2), respectively. Yes. As described above, when the inscribed ellipse is generated and displayed in the circumscribed rectangle, all the rectangular areas determined to have smoke by the smoke detecting unit 20 are included in the inscribed ellipse, and thus the area where smoke is generated accurately. Can be shown on the monitor.

  Then, the smoke type display processing means 32 finally displays the ellipse generated as shown in FIGS. 2 (b1) and 2 (b2) on the monitor as shown in FIG. 2 (c). In FIG. 2C, two ellipses generated corresponding to the characteristic 1 are indicated by a one-dot chain line, and one ellipse generated corresponding to the characteristic 2 is indicated by a two-dot chain line. As shown in FIG. 2 (c), the smoke type display processing means 32 can display an ellipse in a different form for each characteristic, and cope with different characteristics even when smoke having a plurality of characteristics is detected in one region. Ellipses can be displayed so that the ellipses are partially wrapped.

  The smoke type display processing means 32 displays on the monitor 2 not only the line type (line shape and line thickness) but also different colors depending on the characteristics on the actual monitor. Thus, visibility can be improved.

  Next, a display form different from that in FIG. 2 will be described with reference to FIG. In FIG. 2 (a1), the smoke type display processing means 32 has created two separate ellipses for two regions that are a group of adjacent regions relating to the characteristic 1. On the other hand, in FIG. 3 (a1), the smoke type display processing means 32 integrates a group of adjacent areas having the same characteristics that exist at intervals of a predetermined distance or less, although not all areas are adjacent to each other. Thus, one ellipse is generated. Thus, visibility can be improved by making a plurality of elliptical displays having the same characteristics into one elliptical display.

  The predetermined distance can also be set as an individual value for each characteristic. Also, even for the same characteristics, different values can be set according to the position of the region. Values individually set in this way are stored in advance in a storage unit not shown in FIG.

  In addition, when there are two groups of areas determined to have smoke by the smoke detection unit, for example, and these grouped areas are separated from each other by a predetermined distance, it is determined whether to connect based on the predetermined distance. However, if the other area is on the extension line in the vertical direction or horizontal direction of one area, the processing is performed in a direction in which the groups are integrated.

  As described above, according to the first embodiment, an ellipse corresponding to the position and size of the mapping result of each region detected for each characteristic is generated, and imaging is performed with different display colors or different line types for each characteristic. A detection result display processing unit for displaying an ellipse on the image monitor screen is provided. As a result, smoke detection results having different characteristics can be easily visually confirmed on the monitor, and visibility can be improved.

  Note that the method of generating an ellipse by the smoke type display processing means 32 is not limited to that based on the circumscribed rectangle. For example, the smoke type display processing means 32 can generate an ellipse by obtaining the center of gravity and the radius from the position and number of adjacent areas mapped.

  In this embodiment, for the area determined to have smoke by the smoke detection unit, the circumscribed rectangle of the area is specified, an ellipse is generated so as to be inscribed in the rectangle, and the ellipse is displayed. . For such a display method, it is also possible to color-display only a small rectangular area determined to have smoke. However, the position and density of smoke is likely to change due to the influence of wind or the like, and even if it is determined that there is smoke at a certain time, it may be determined that there is no smoke after a few seconds.

  As described above, by specifying the circumscribed rectangle of the area and generating an ellipse so as to be inscribed in the rectangle, all the areas determined to have smoke can be included (enclosed) in the ellipse. However, the merit of this display method is that the ellipse is displayed in a state including the area determined as having no smoke. For this reason, it is possible to display so that it is easy to imagine how much smoke is in the monitoring area being monitored.

  Incidentally, the detection area may be masked by a mask function. When thin, slowly diffusing smoke is detected by the thin smoke detection algorithm, the slow smoke moves from the bottom to the top and tends to stay near the ceiling. If the detection area is set so that only the vicinity of the ceiling is observed after processing, the influence of passersby can be reduced. It should be noted that with respect to the dark slow smoke, the same mask setting may be performed on the assumption that the behavior is similar to that of the thin slow smoke.

  In addition, since fluid smoke is generated from the vicinity of the fire source that exists at the bottom of the screen, a detection area is set at the bottom of the screen rather than at the top of the screen, and the upper detection area is masked. If it is made to perform, it becomes easy to detect the flowing smoke which becomes object, and it can make it difficult to produce misinformation.

  DESCRIPTION OF SYMBOLS 1 Camera, 2 Monitor, 10 Image memory, 20 Smoke detection part, 21 Flowing smoke detection means, 22 Dark slow smoke detection means, 23 Thin slow smoke detection means, 30 Detection result display processing part, 31 Mapping means, 32 Smoke type display Processing means.

Claims (3)

Smoke detection means for identifying and detecting a plurality of types of smoke having different characteristics by having two or more smoke detection determination elements for each of a plurality of areas set in an image captured by a surveillance camera In the provided smoke detection device,
Mapping means for mapping the area in which smoke is detected by the smoke detection means among the plurality of areas according to characteristics;
Based on the mapping result for each characteristic by the mapping means, an ellipse is generated according to the position and size of the mapped region corresponding to each characteristic, and the image captured by the monitoring camera is displayed on the monitor And a smoke type display processing means for displaying the generated ellipse in a different color or a different line type corresponding to each characteristic. The smoke detection device according to claim 1,
The smoke type display processing means identifies a circumscribed rectangle of an adjacent area mapped corresponding to each characteristic, and generates the ellipse so as to be inscribed in the identified circumscribed rectangle apparatus. The smoke detection device according to claim 2,
The smoke type display processing means identifies a circumscribed rectangle of an area obtained by integrating adjacent areas mapped corresponding to respective characteristics and areas existing at intervals of a predetermined distance or less, and inscribes the identified circumscribed rectangle The smoke detection device is characterized by generating the ellipse as described above.

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